1. Field of the Invention
The present invention relates to disc defect management, and more particularly, to a disc in which a temporary defect management information area and a temporary management area are formed, and a method and apparatus for managing a defect in such a disc.
2. Description of the Related Art
Defect management is performed to allow a user to rewrite user data of a portion of a user data area in which a defect occurs in a new portion of the user data area of a disc, thereby compensating for a loss in data caused by the defect. In general, defect management is performed using linear replacement or slipping replacement methods. In the linear replacement method, a user data area in which a defect occurs is replaced with a spare data area having no defects. In the slipping replacement method, a user data area having a defect is slipped to use the next user data area having no defects.
Both linear replacement and slipping replacement methods are applicable only to discs such as a DVD-RAM/RW on which data can be repeatedly recorded and recording can be performed using a random access method. In other words, the conventional linear replacement and slipping replacement methods cannot be applied to write-once discs on which recording is allowed only once. In general, the presence of defects in a disc is checked by recording data on the disc and confirming whether the data can be recorded on the disc. However, once the data is recorded on a write-once disc, it is impossible to overwrite new data and manage defects therein.
Meanwhile, after the development of CD-R and DVD-R, a high-density write-once disc having a recording capacity of several dozen of GB has been introduced. This type of disc can be used as a backup disc since it is not expensive and allows random access, which enables fast reading operations. However, defect management is not available for write-once discs. Therefore, a backup operation is discontinued when a defective area (i.e., an area where a defect occurs) is detected during the backup operation because defect management on a write-once disc cannot be performed.
In general, the backup operation is performed when a system is not frequently used. Thus, backup operations are often performed at night when a system manager does not operate the system. In this case, it is more likely that the backup operation will be stopped because a defective area of a write-once disc is detected and the backup operation for the system will therefore not be performed in a reliable manner.